I have to weld up some patches in the floor of my 1965 C10. I've been welding with an old Lincoln arc welder for many years, but I've always been standing on the floor. With the floor patches it looks like I will have to get in the truck to weld some of them. I have a 1/2" thick rubber pad I can sit on in needed. My question is do I have to be grounded to the floor since the truck is on rubber tires?

I just don't want to electrocute myself, lol!

Thanks
Larry